Prime factorization is the expression of a natural number greater than one as a unique product of prime numbers.

The number 40 can be written in prime factorization as 2 x 2 x 2 x 5. All of the factors are prime numbers.

Using exponential form, 40 = 2³5¹, indicating that there are three 2's and one 5 multilplied together to get the result of 40.